A INSERT SQL is MySQL use memory too much

[问问 jack]

when MySQL is running a insert data, the count of number is about 20w, and is about 100M but the memory useage is about more than 4G


*************************** 1. row ***************************
thread_id: 442974
event_name: memory/sql/THD::variables
sys.format_bytes(CURRENT_NUMBER_OF_BYTES_USED): 3.93 GiB
sql_text: INSERT INTO data
the SQL memory from SELECT a.thread_id, a.event_name,sys.format_bytes(CURRENT_NUMBER_OF_BYTES_USED), sql_text FROM performance_schema.memory_summary_by_thread_by_event_name a,performance_schema.events_statements_current b where a.thread_id=b.thread_id ORDER BY CURRENT_NUMBER_OF_BYTES_USED DESC LIMIT 10; CURRENT_NUMBER_OF_BYTES_USED is about 3GB

is there any wrony with it ?